The present invention relates to on-board vehicle controllers. More specifically, the present invention relates to an on-board vehicle control method and apparatus that is able to transfer data between electronic devices such as remote development, diagnostic, and software tools and on-board vehicle controllers.
An area in the auto industry seeing tremendous change from past practices is the area of control and communication in automotive vehicles. The creation of relatively inexpensive microprocessors and the digital revolution have put the power of advanced electronics and communications into the hands of automotive engineers. Controllers, microprocessors, and other electronic devices control and monitor various systems in a vehicle such as the transmission, the internal combustion engine, braking systems, and other related systems. The information stored on the controllers in the vehicle must be accessed by remote electronic devices such as development, diagnostic, and software tools (xe2x80x9ctoolsxe2x80x9d) during testing and programming. The tools are used to monitor and modify vehicle process variables and other vehicle data during testing and maintenance activities. The vehicle process variables and data indicate if the on-board electronic systems of the vehicle are functioning correctly and also control certain vehicle functions.
Vehicle controllers storing various vehicle process variables and data may be required to interface with a myriad of tools having numerous communication protocols. The communication protocols may vary from tool to tool as a function of manufacturer, and from vehicle controller to vehicle controller as a function of vehicle makes, models, or model years. Conventional vehicle controllers have limited communication flexibility and are only capable of communicating with a limited amount of tools under a specific communications protocol. In certain testing situations, more than one tool may be required for diagnostic testing of an automotive vehicle, and a vehicle controller will be required to communicate under numerous communications protocols to the tools. Presently, special external hardware and custom-made instrumentation is connected to a vehicle controller to trigger special logic embedded in the vehicle controller, generating a complex memory overlay process to allow tools to have access to the memory of the vehicle controller. This additional custom-made instrumentation may be unreliable, expensive, and difficult to maintain.
Furthermore, a number of present tools and vehicle controllers are rigidly pre-programmed for the types and amount of data that may be transferred between them. Accordingly, because of the limited flexibility of present day tools and vehicle controllers, there is a need for a dynamic adaptable method and apparatus to transfer information between a tool and a vehicle controller.
In accordance with the present invention, an on-board vehicle controller includes a processor/communication protocol independent method and apparatus to simultaneously support the concurrent use of multiple tools to monitor the state of memory locations in the vehicle controller at multiple transmission rates. The vehicle controller includes software to interface with remote development, diagnostic, and software tools having multiple communications protocols. The vehicle controller includes communications specific hardware and software that is able to receive and transmit information over a plurality of standard communication protocols such as IES-CAN, GMLAN, KWP2000, J1850, and J1939. The communication link specific software is contained in a first datalink/network layer that interfaces to a second applications layer which is functionally independent of the communications protocol.
The vehicle controller of the present invention allows tools to request periodic memory transfer from the vehicle controller memory at rates between 1 and 65,535 ms, but any technically feasible data transfer rate is considered within the scope of this invention. The actual data rates are multiples of the rate at which the method or algorithm of the vehicle controller is tasked and are calculated during a data request by a tool. The method of the present vehicle controller supports up to 255 simultaneous tools, allowing more than one tool to share a specific piece of transmitted information if the requested transfer rate and memory location is identical to that of another tool.
The vehicle controller of the present invention has many potential advantages over traditional external hardware-based systems, including reduced cost, reduced down time due to instrumentation hardware issues, increased development productivity due to simplification of the instrumentation and communication systems, and a more easily maintained system, as compared to present systems. In addition, the method of the present invention will reduce start-up time and costs associated with developing a new vehicle controller by eliminating the necessity to maintain several sets of external instrumentation hardware and software.